Brake



July 5, 1932. Y A. Y. DODGE ET AL BRAKE Filed April 4, 1929 INVENTORS glkxjgv' and f1 my or A TTORNEY Adi 01 K UNITED (PATENT; OFFICE ADIEL Y. DODGE, OF SOUTH BEND, INDIANA, AND GEO'IL H. TAYLOR, OF DETROIT, MICHI- GAN, ASSIGNORS TO BENDIX BRAKE COMPANY, OF SOUTH BEND, INDIANA, A GOR- POBATION OF ILLINOIS BRAKE Application flled April 4, 1929. Serial No, 352,353.

This invention relates to brakes, and is illustrated as embodied in an internal ex panding automobile brake. An object of the invention is to provide simple and eflicient means whereby one of two anchored shoes may react on another with a servo effect, to increase its eflectiveness.

Preferably this is accomplished by novel anchorage means for the two shoes or their equivalents, for example a rocking member (shown as triangular in form) mounted on the brake anchor and connecting the shoes in a manner providing the desired interaction. In the illustrated embodiment, the connection to at least one shoe includes two pivots or the like, for example pivot pins carried by the rocking member and seated in notches in the shoe, with one pivot substantially on the drum radius, passing through the anchor. Thus when the thrust is from the shoe to the rocking member there is no tendency to move the heel of the shoe away from the drum and thereby decrease its eiiectiveness, whereas when the thrust is from the rocking member to the shoe there is a substantial component of force radially toward the drum which acts on the heel of the shoe to increase its efi'ectiveness.

I The above and other objects and. features of the invention, including various novel and desirable details of construction, will be apparent from the following description of the illustrative embodiment shown inthe accompanying drawing, in which:

Figure 1 is a section vertically through the brake, just inside the head of the brake drum,

7 and showing the brake shoes in side eleva- 4o *"bo tbmsp n w bm a lf I .'Fig'ure2 is' a partial section on the line 22 of ylg ure l, showing 'the novel anchorage in "1 thearrangment 1 maimed; and which I may beregarded as iii-some respects an imdrum 10, a support such as a backin provement on the construction of applica- Y1? Dodge, the brake includes a rotatable plate 12 at the open side of the drum, and riction means within the drum and preferably in-' cluding three shoes or the like 14, 16, and 18 arranged end to end. The primary shoe 14 is shown connected to the secondary shoe 16 by means such as a floating pivot 20. The brake is-applied, against the'resistance of a return spring 22, by means such as a double cam 24 actingdirectly on the primary and auxiliary shoes 14 and 18, and acting through the primary shoe 14 to apply the secondary shoe 16 against the resistance of an auxiliary return spring 26. The drum turns counterclockwise when the automobile is moving forward. 1 a

The present invention relates to a novel anchorage for shoes 16 and 18 or their equivalents. Preferably there is a single fixed anchor, such as a post 30 carried by the backing plate and secured thereto by means such as a nut 32, and which is arranged between the adjacent ends of the shoes. Pivoted on this anchor is a rocking member such as a triangular plate 34 having its apexmounted on the anchor, and which may be connected adjacent its upper base angle to the end of shoe 18 by I means such as a pivot 36.

The particular form of connection between the rocking member 34 and the shoe 16 which is shownin the drawing includes a pair of pivot pins 38 and 40 carried by the rocking member 34 and seated in notches adjacent the end of shoe 16, the shoe being urged against these pivots by means such as a spring 42. Pivot 38 is arranged adjacent the lower base angle of the rocking member 34, while pivot 40 is arranged substantially on the drum radius passing through anchor30 and approximately at the center of the base of member 34.

If the drum is turning counter-clockwise,

in its normal direction of rotation, when the brake is applied, shoe 16 thrusts against the rocking member 34 through pivot 40, pivot 38 swinging idly out of its notch. Thus while If the drum is turning clockwise, shoe 18 turns member 34 to cause pivot 38 to thrust the heel of shoe 16 radially toward the drum, thus greatly increasing its effectiveness, the pivot 40 being idle at this time. The heel of shoe 18 does in this case have a slight tendency to move away from the drum, but the a loss of effectiveness due to this is much less ing member connected to the adjacent ends of said shoes and whose connection to at least one of the shoes is by a. pair of alternativelyelfective parts, one of which transmits thrust from the shoe to the rocking member substantially without radial movement of the shoe with respect to the drum when the drum is turning in one direction, and the other of which transmits thrust from the rocking I member to said shoe with a substantial component radially toward the drum when the drum is turning in the other direction.

2. A brake comprising, in combination, a drum, a. pair of shoes engageable with the drum, and a rocking member connected to said shoes and whose connection to at least one of the shoes is by a pair of alternativelyetfective parts, one of which transmits thrust from the shoe to the rocking member substantially without radial movement of the shoe with respect to the drum when the drum is turning in one direction, and the other of which transmits thrust from the rocking member to said shoe with a substantial component radially toward the drum when the drum is turning in the other direction.

3. A brake comprising, in combination, a drum, a pair of friction members'adjacent the drum, an anchor, agenerally triangular rocking member pivoted at its apex on the anchor and connected to one of the friction members and a'connection between the rocking member and the other friction member including a pair of pivots carried by" one of said last mentioned connected members and seatedin notches in the other of said members and one of which is arranged substantially on the drum radius passing through the anchor.

4. A. brake comprising, in combination, a drum, a pair of friction members adjacent the drum, an anchor, a enerally triangular rocking member pivote at'its apex on the anchor and connected to'one of its friction members and a connection between the rocksaid last mentioned connected members and Zeated in notches in the other of said memers.

5. A brake comprising, in combination, a

drum, a pair of friction members adjacent the drum, an'anchor, a generally triangular rocking member pivoted at its apex on the anchor and connected to one of the friction members, and a pair of connections between the rocking member and the other friction member, one of which is arranged substantially on the drum radius passing through the anchor. 6. A brake comprising, in combination, a drum, a pair of friction members adjacent the drum, an anchor, a generally triangular rocking member pivoted at its apex on the anchor and connected to one of the friction members, and alternating means connecting the rocking member and the other friction member.

7. A brake anchorage having pivoted thereon at its apex a triangular rocking member having pivots adjacent its base angles and another pivot adjacent the center of its base.

8. A brake comprising a support,a pair of brake shoes thereon, and an anchor member having at least four pivotal connections to the shoes and the support.

9. A brake comprising a support, a pair of brake shoes having an anchorage to the support including a rocking member pivoted to each shoe and the connection to one shoe being through a plurality of pivots.

10. A brake comprising a brake shoe, and an anchorage therefor having two pivotal connections with the shoe, said pivotal connections being adapted to be alternatively actuated by reversals in the brake retarding force.

11. A brake comprising a shoe and an anchorage therefor including a member having two pivotal connections with the shoe each of which is rockable to a non-pivotal position when the other is pivotally operate 12. A brake comprising a shoe anchored by a pair of spaced pivots so arranged that a pivotal movement about either moves the other to an inoperative position.

18. A brake comprising a shoe anchored by a pair of relatively fixed journals engaged by a pair of relatively fixed bearin s having a separable relation to both journa s.

In testimony whereof, I have hereunto signed my name.

CECIL H. TAYLOR.

In testimony whereof, I have hereunto 

